LCD (liquid crystal display) color is implemented by color filters (CF). However, traditional color filters have disadvantages such as a poor utilization of light, a low transmittance, a wide transmission peak for traditional color block material, a limited color density, and a difficulty to achieve wide color gamut, and thus cannot satisfy users demand to display quality. Quantum Dots (QDs) are spherical semiconductor nano-particles composed of Group II-V or Group III-V material. Particle size typically is in a range of a few nanometers to tens of nanometers. Due to a smaller half width and height of an emission peak and an easy adjustment to the color of the emitting light by means of adjusting the size, structure or composition of the quantum dot material, the quantum dot material can be used in a display device to effectively improve the color saturation and color gamut of a display device.
Quantum dot material can absorb blue light of short-wavelength and emit light of long-wavelength. This feature makes the blue light emitted by the blue backlight present red, green and other colors after being projected onto the quantum dot material. The current color filter of quantum dot can be divided into a blue filter portion, a red filter portion and a green filter portion. The red filter portion and the green filter portion are filled with quantum dot material that allows the user to receive red light or green light at all angles. The blue filter is usually filled with transparent material, or even nothing, for needs to transmit blue light. This will lead to appear a color deviation problem in the blue filter due to different viewing angles.
In order to improve the color deviation of the blue filter due to a viewing angle, a conventional method is to insert a black filter into the blue filter portion. However, this makes the transmittance of the blue filter portion decrease, which is not good for increasing an aperture ratio of the blue filter portion.